The present invention relates to fuel systems, and more specifically to fuel systems, such as diesel fuel systems, that separate, monitor, and require disposal of water that accumulates therein.
Water accumulates in fuel storage tanks, as well as in the fuel tanks on vehicles such as cars, trucks, buses, boats, construction equipment and on other mobile and stationary engines. The presence of water in fuel tanks can be attributed to a variety of causes, such as ground water seepage, rain water collection, and condensation of water from air.
Engine fuel systems, particularly diesel fuel systems, include a fuel filtration system for separating the water from the fuel. The fuel filtration system may also include a way to monitor how much water has been collected so that the water can be periodically purged by, for example, opening a drain valve. A vehicle operator is alerted to the need to drain the water collected by the fuel filtration system by the illumination of a warning light on the dashboard of the vehicle.
If a vehicle operator ignores the warning light and fails to periodically purge the fuel filtration system of water, then the water backs-up and eventually overflows into the fuel system of the engine. If the engine continues to run allowing water to run through the fuel system, rust builds up and eventually leads to internal engine damage.
Warranty claims are often made on failed fuel injection pumps. Only after payment of such a claim, does a pump supplier remove the fuel injection pump, tear it down, and then discover internal rusting. Thus, the need exists for a way to detect fuel-in-water abuse without disassembly of the engine. The present invention meets this need in a novel and unobvious way.
The present invention utilizes a software program and a water sensor in the vehicle""s fuel filtration system to monitor if the vehicle operator ignores the conventional dashboard warning light and continues to operate the engine when water is present in the fuel filtration system. In one embodiment of the present invention, the program detects chronic abuse by calculating the total duration of vehicle operation while the water-in-fuel dashboard warning light is illuminated. The duration of abuse can be calculated in terms of either distance traversed or time elapsed. In an alternative embodiment, the program records single-event abuse which occurs when the operator neglects the water-in-fuel warning light for one extended period of time.
A distance or time threshold is chosen, and, once exceeded, the software program writes a permanent fault code to the engine control memory. A diagnostic tool applied to the engine control memory is capable of reading the fault code stored therein. The absence of the fault code permits an engine manufacturer to conclude that warranty coverage is justified; whereas, the presence of the fault code reveals that the vehicle operator ignored the water-in-fuel indicator and neglected to purge the water from the fuel filtration system. The fault code permanently remains in the engine control memory in order to retain a history of engine abuse in the event of changes in vehicle ownership.
One feature of the present invention is a system for detecting water-in-fuel abuse that includes a fuel filter, a means for detecting if water located therein reaches a certain level, and means for determining the duration that water is detected at or above that level. The system may also include means for recording if the duration exceeds a threshold.
Another feature of the present invention is a method for detecting water-in-fuel abuse that includes providing a fuel filter, detecting if the water level in the filter reaches a certain level, and calculating the duration that the water level is at or above that level. The method may additionally include writing a fault code to permanent memory if the duration exceeds a threshold.
Another form of the present invention uses the software program to count the number of events of water-in-fuel abuse (i.e., the number of times that the water-in-fuel dashboard warning light has been illuminated). A still further form of the present invention determines the longest duration of any single event of water-in-fuel abuse. These data may be written to permanent memory. A diagnostic tool is capable of accessing these data stored in permanent memory.
Accordingly, one object of the present invention is to provide a unique way of detecting fuel-in-water abuse.
Related objects and advantages of the present invention will be apparent from the following description.